WOMEN with HIV (especially minority

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c 2007 Lippincott Williams & Wilkins, Inc.

RESEARCH LETTERS

Women With HIV and Stigma

Elizabeth Abel, PhD, RN

W

OMEN with HIV (especially minority women) are the fastest-growing HIV population,¹ and they often experience the stigma of HIV within the context of poverty.² Gray³found that the fear of HIV-related stigma was more of a concern than the fear of dy- ing among women with HIV. The devastating consequence of HIV-related stigma and the need for interventions have been highlighted elsewhere.⁴

HYPOTHESIS

Women living with HIV who participate in an emotional writing disclosure (EWD) intervention will demonstrate an improved perception of HIV-related stigma compared to women in a control group. EWD is based on the assumption that putting traumatic events into words helps people organize, make sense of, and ultimately reduce intrusive thoughts, a process called cognitive reorganization.

EWD has shown social, physiological, and emotional benefits.^5–10

From the School of Nursing, The University of Texas at Austin.

This research was supported by the NINR, NIH Center for Health Promotion Research at The University of Texas at Austin School of Nursing (P30NR005051). The author thanks J. Pennebaker, PhD, and C. Brown, PhD (coinvestigators) and C. Delville, MSN, CNS, and L. Hob- son, MSW (Research assistants).

Corresponding author: Elizabeth Abel, PhD, RN, School of Nursing, The University of Texas at Austin, TX 78701 (e-mail: eabel@mail.utexas.edu).

METHODS

In this Institutional Review Board-approved pilot study, an experimental design evaluated the impact of EWD on self-perceived HIV-related stigma in women.

Recruitment

Three community peer-leaders (African American, Hispanic, and White women) were hired to aid with recruitment/retention from sites that provided services to women with HIV. Participants were compensated for their time and travel. Some were randomly assigned to an experimental group where they wrote about their feelings related to having HIV; others were assigned to a control group where they wrote on a neutral topic for 3 consecu- tive days for 20 minutes each day. Power analysis of .80 with 2-tailed alpha level of .05 re- quired 20 for each group—based on the effect size of earlier EWD studies.¹¹

Measurement tools

Women were prescreened for health literacy, cognitive capacity, and physical stamina.^12–15 Three women were unable to meet these criteria. Once women with HIV met prescreening criteria, they were included if they were 18 years or older, on antiretroviral drugs, had no major illnesses, were able to speak and write English, and consented to be in the study. All women had 6 contacts: questionnaires on perception of stigma on visit 1 (week 1); writing on visits 2 through 4 (week 1); and stigma questions at visit 5 (week 6) and at visit 6 (week 12).

Linguistic Inquiry and Word Count (LIWC), S104

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Research Letters S105 a text analysis software program, evaluated

the cognitive reorganization illustrated in the writing for both groups. Average intervention essays contained 2% negative emotion words and 3.1% positive emotion words, compared with 0.6% negative and 1.2% positive emotion words in control groups.¹⁶The Stigma Scale, designed for individuals diagnosed with HIV/AIDS, consisted of 13 items on a 1 to 4 ordinal scale that evaluated fear, avoidance, and perceived negative responses related to HIV status.¹⁷ This scale demonstrated an adequate average reliability score for the 3 contacts at weeks 1, 6, and 12 (α=.87).

SAMPLE

Participants were older than expected; experimental group (n = 21) average age was 43 years, control (n = 23) group’s was 45.

The average education was the 12th grade for both groups. Seventy-four percent of the participants were African American, suggestive of an ethnically representative sample.

RESULTS

The experimental group compared with the control group reported greater cognitive reorganization (F =14.235,P =0.001) and significantly improved perceived HIV-related stigma scores from visit 1 (week 1) to visit 6 (12 weeks) (Wilks=0.178,P=0.018).

DISCUSSION

The study showed a positive influence on perception of stigma. Further studies with a larger sample, over a longer time, and with a booster are suggestions for the future. Con- siderations should address the potential for contamination between the 2 groups; participants who knew each other likely discussed the study, despite instructions to the contrary.

EWD, an inexpensive and convenient intervention that changed the perception of stigma positively for women with HIV in the experimental group, is a promising finding to advance the health of women.

REFERENCES

1. Centers for Disease Control and Prevention.

HIV/AIDS surveillance report: cases of HIV infection and AIDS in the United States, 2003. Available at:

http://www.cdc.gov/hiv/stats/hasrlink.htm. Access- ed December 18, 2004.

2. Andrews S. Social support as a stress buffer among human immunodeficiency virus-seropositive urban mothers.Holistic Nursing Practice. 1995;10(1):36–

43.

3. Gray JJ. The difficulties of women living with HIV infection.Journal of Psychosocial Nursing and Men- tal Health Services. 1999;37(5):39–43.

4. Brimlow DL, Cook JS, Seaton R. Stigma & HIV/AIDS:

a review of the literature. Rockville, MD: Health Re- sources and Services Administration, HIV/AIDS Bu- reau; 2003.

5. Esterling BA, Antoni MH, Fletcher MA, Marguiles S, Schneiderman N. Emotional disclosure through writing or speaking modulates latent Epstein-Barr virus antibodies titers.Journal of Consulting and Clinical Psychology. 1994;62(1):130–140.

6. Pennebaker JW. Writing about emotional experiences as a therapeutic process. Psychological Sci- ence. 1997;8(3):162–166.

7. Pennebaker JW. The social, linguistic, and health con- sequences of emotional disclosure. In: Suls J, Wallston KA, eds.Social Psychological Foundations of Health and Illness. Malden, MA: Blackwell; 2003:288–

313.

8. Pennebaker JW, Mayne TJ, Francis ME. Linguistic pre- dictors of adaptive bereavement.Journal of Personal and Social Psychology. 1997;72(4):863–871.

9. Smyth JM, Stone AA, Hurewitz A, Kaell A. Effects of writing about stressful experiences on symptom reduction in patients with asthma or rheumatoid arthri- tis: a randomized trial.JAMA. 1999;281(14):1304–

1309.

10. Petrie KJ, Fontanilla I, Thomas MG, Booth RJ, Pen- nebaker JW. Effect of written emotional expression on immune function in patients with human immunodeficiency virus infection: a randomized trial.Psy- chosomatic Medicine. 2004;66:272–275.

11. Freedman LS. Tables of the number of patients re- quired in clinical trials using the logrank test.Statis- tics in Medicine.1982;1:121–129.

12. Davis TC, Long SW, Jackson RH, et al. Rapid estimate of adult literacy in medicine: a shortened screening instrument.Family Medicine. 1993;25(6):391–395.

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13. Davis TC, Michielutte R, Askov EN, Williams MV, Weiss BD. Practical assessment of adult literacy in health care. Health Education & Behavior.

1998;25(5):613–624.

14. Kaufmann DM, Weinberger M, Strain JJ, Jacobs JW.

Detection of cognitive deficits by a brief mental status examination: The Cognitive Capacity Screening Ex- amination, a reappraisal and a review.General Hos- pital Psychiatry. 1979;1(3):247–255.

15. Karnofsky DA, Abelmann WH, Craver LF, Burchenal

JH. The use of the nitrogen mustards in the palliative treatment of carcinoma.Cancer. 1948;1:634–656.

16. Pennebaker JW, Francis M.Linguistic Inquiry and Word Count: LIWC. Mahwah, NJ: Erlbaum; 2001.

17. Sowell RL, Cohen L, Demi A, Moneyham L.Family Responses to HIV/AIDS Infection: Stressors, Resis- tance Factors, and Adaptational Outcomes(Fam- ily Coping Project). Atlanta, GA: Centers for Disease Control and Prevention; 1992. Cooperative Agree- ment #U64/CCU408293.

The Extent of Substance Use Problems Among Women

Partner Abuse Survivors Residing in a Domestic Violence Shelter

Dawnovise Fowler, PhD

C

OOCCURRENCE of intimate partner abuse (IPA) and substance use problems, often leading to injury, disability, poor health, mental illness, and even death, is estimated at 38%–85% in various samples of women.^1–3 Compared to women who have not experienced IPA, women survivors of IPA are more likely to abuse drugs and alcohol,^4–6 and receive prescriptions for and become dependent on drugs.⁷ Their substance abuse may also place them at risk for subsequent victimization.^4,8Less is known about how to provide services to treat their substance abuse problems. Women in general may underutilize substance abuse treatment services,⁹ but do-

From the School of Social Work, The University of Texas at Austin.

Corresponding author: Dawnovise Fowler, PhD, School of Social Work, The University of Texas at Austin, TX 78701 (e-mail: dfowler@mail.utexas.edu).

mestic violence shelters, a primary source of help for IPA women survivors, have either no or limited substance abuse assessment methods and intervention, which results in discon- tinuous, fragmented service delivery.

PURPOSE

This study assessed the extent of substance use problems (incidence, risk, and type of substance abuse) among a domestic violence shelter–based sample of IPA women survivors.

METHODS

Shelter staff noted drug or alcohol problems in 50% of client files, according to a review of client records. However, no standardized screening procedures were in place. Thus, while it is possible that substance use incidence is overestimated, it is hypoth- esized that the lack of systematic screening makes this figure an underestimate.

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Research Letters S107 Individual interviews were conducted by

using in-depth questionnaires and assessment on substance use problems and partner abuse.

The CAGE^∗-AID (CAGE adapted to include drugs) was used to screen for potential substance use problems.¹⁰ This brief screening tool is widely used and requires less than a minute to complete and score, which makes it suitable for use in crisis-oriented environ- ments. Risk levels for substance abuse and use during the past 30 days were measured with the Simple Screening Instrument for Alco- hol and Other Drug Use¹¹ and the Addiction Severity Index (ASI),¹²respectively. Substance use disorders were diagnosed using module E of the Structured Clinical Interview for DSM-IV-TR Axis I Disorders (SCID-IV).¹³ The Partner Abuse Scale-Physical (PASPH) and the Partner Abuse Scale-Non-physical (PASNPH) are 25-item instruments designed to measure the severity of problems with physical (including sexual) and nonphysical abuse in a dyadic relationship.¹⁴Both instruments take approximately 5 minutes to complete, and show high reliability with a Cronbach’sαof .90.

SAMPLE

New intakes and current shelter residents, all women survivors seeking refuge from IPA, were recruited. One hundred two women participated in the study. Participants ranged from 18 to 62 years old, with a mean age of 35 (SD=10.36). Most had children (average of 2 children). Approximately 30% had a high school diploma; 8.9% had a college degree.

The sample was predominantly lower income (eg, 81% earned up to $10,000).

RESULTS

Using SPSS, descriptive and correlational statistics were used to analyze the data. Eighty participants scored positive for further need

∗CAGE indicates Cutting down Annoyance by Criticism, Guilty Feeling, and Eye-openers.

for substance abuse assessment; 67.7% scored from moderate to high in the degree of risk for substance abuse. More than 75% reported ever using cocaine. More than 80% reported ever using cannabis, 10.8% reporting use in the past 30 days. Nearly 60% were alcohol dependent, and 55% were drug dependent. Co- caine use in the past 30 days was significantly related to physical partner abuse (r = 0.27, P= 0.05). In addition, the number of years of alcohol use was also significantly related to physical partner abuse (r=0.25,P=0.05).

DISCUSSION/IMPLICATIONS

Findings are consistent with other studies on substance use problems among IPA women survivors. Likewise, the incidence rates are 5% to nearly 18% higher regarding the risk for substance abuse and dependence in this study than the substance use problems originally noted in the clients’ files. Also, significant relationships between physical partner abuse and specified substance use support theoretical perspectives on why women survivors use substances (to self-medicate from physical injury, increased vulnerability to IPA as a result of preceding substance use). Overall, these findings support the need for shelter-based substance abuse assessment and intervention. Effective substance abuse assessments and interventions that are shelter- based advances services and treatment¹⁵ by more comprehensively meeting their needs for cooccurring, entangled problems.

FUTURE RESEARCH

Post hoc analyses will be conducted to determine predictive relationships between psychosocial variables, partner abuse, and substance abuse. In the pilot, the effects of a standardized substance abuse intervention to decrease alcohol consumption and/or stop drug use among IPA women survivors with substance use problems will be compared to effects among a standard care group in the shelter. Pilot data will inform a federal application for a larger study.

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REFERENCES

1. El-Bassel N, Gilbert L, Witte S, et al. Intimate partner violence and substance abuse among minority women receiving care from an inner-city emergency department. Women’s Health Issues. 2003;13:16–

22.

2. Stuart G, Moore T, Ramsey S, Kahler C. Hazardous drinking and relationship violence perpetration and victimization in women arrested for domestic violence.Journal of Studies on Alcohol.2004;65(1):

46–53.

3. Weinsheimer R, Schermer C, Malcoe L, Balduf L, Bloomfield L. Severe intimate partner violence and alcohol use among female trauma patients.Journal of Trauma.2005;58(1):22–29.

4. El-Bassel N, Gilbert L, Schilling R, Wada T. Drug abuse and partner violence among women in methadone treatment.Journal of Family Violence.

2000;15(3):209–228.

5. McFarlane J, Malecha A, Gist J, et al. Intimate partner sexual assault against women and associated victim substance use, suicidality, and risk factors for femi- cide.Issues in Mental Health Nursing.2005;26:953–

967.

6. Morgenstern J, McCrady B, Blanchard K, McVeigh K, Riordan A, Irwin T. Barriers to employabil- ity among substance dependent and nonsubstance- affected women on federal welfare: implications for program design. Journal of Studies on Alcohol.

2003;239–246.

7. Stark E, Flitcraft A. Violence among intimates: an epi- demiological review. In: Hasselt V, Morrison R, Bel- lack A, Hersen M, eds.Handbook of Family Violence.

New York: Plenum; 1988:293–297.

8. Kilpatrick D, Acierno R, Resnick H, Saunders B, Best C. A two-year longitudinal analysis of the relationships between violent assault and substance use in

women.Journal of Consulting and Clinical Psychol- ogy.1997;65(5):834–847.

9. Substance Abuse and Mental Health Services Admin- istration (SAMHSA).Results From the 2001 National Household Survey on Drug Abuse: Summary of Na- tional Findings. Rockville, MD: Office of Applied Studies; 2001:1. NHSA Series H-17, DHHS Publication No. SMA 02-3758.

10. Brown R, Rounds L. Conjoint screening questionnaires for alcohol and other drug abuse: criterion va- lidity in a primary care practice.Wisconsin Medical Journal .1995;94(3):135–140.

11. Substance Abuse and Mental Health Services Admin- istration (SAMHSA).Simple Screening Instruments for Outreach for Alcohol and Other Drug Abuse and Infectious Diseases. Rockville, MD: Center for Substance Abuse Treatment; 2003. Treatment Im- provement Protocol Series 11, DHHS Publication No.

(SMA) 03-3803.

12. McLellan A, Luborsky L, Woody G, O’Brien C. Im- proved diagnostic instrument for substance abuse patients: The Addiction Severity Index. The Jour- nal of Nervous and Mental Disease.1980;173:412–

423.

13. First M, Spitzer R, Gibbon M, Williams J.User’s Guide for the Structured Clinical Interview for DSM-IV Axis I Disorders—Clinical Version (SCID-CV). Wash- ington, DC: American Psychiatric Press; 1997.

14. Hudson W.Partner Abuse Scales: Physical and Non- Physical. Tempe, AZ: Walmyr Publishing; 1992.

15. Ogle R, Baer J. Addressing the service linkage problem: increasing substance abuse treatment en- gagement using personalized feedback interventions in heavy-using female domestic violence shelter residents. Journal of Interpersonal Violence.

2003;18(11):1311–1324.

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Research Letters S109

HIV Prevention Targeting African American Women

Theory, Objectives, and Outcomes From an African-centered Behavior Change Perspective

Dorie J. Gilbert, PhD, MSSW; Lawford Goddard, PhD

A

FRICAN AMERICAN (AA) women ac- counted for 69% of estimated new HIV diagnoses among US women from 2000 to 2003, although AAs constitute only 13% of the US population. The rate of AIDS diagnoses for AA women is 23 times that for White women.

HIV/AIDS is the leading cause of death for AA women 25–34 years old, with hetero- sexual transmission (sex with injection drug users, bisexual men, and with an HIV-infected person with an unidentified risk) compris- ing approximately 78% of HIV exposure. An- other 19% is due to women’s injection drug use.¹

Early prevention messages, targeted primarily at gay, White men, did little to impact the AA community and failed to acknowl- edge how poverty, institutional racism, a bi- ased criminal justice system, disenfranchisement, and gender inequality contribute to the disproportionate number of HIV infection cases among AA women.²Culturally tai- lored prevention programs should, at mini- mum, emphasize the cultural competencies of researchers and helping professionals and

From the School of Social Work, The University of Texas at Austin (Dr Gilbert); and Institute for the Advanced Study of Black Family Life and Culture, Oakland, Calif (Dr Goddard).

The research was funded by the Substance Abuse and Mental Health Services Administration (SAMHSA).

Corresponding author: Dorie J. Gilbert, PhD, MSSW, School of Social Work, The University of Texas at Austin, TX 78701 (e-mail: djm@mail.utexas.edu).

include salient beliefs, language, traditions, worldviews, and values.³ Programs for AA women were developed beginning in the mid-1990s⁴and continue to use cultural- and gender-appropriate materials to build ethnic pride and incorporate cultural- and gender- specific themes to promote condom use.⁵ This report presents the types of outcome measures targeted by an African-centered HIV prevention program as compared to prevention programs targeting behavior change as measured primarily through condom use.

THE AFRICAN-CENTERED BEHAVIORAL CHANGE MODEL

The African-Centered Behavioral Change Model (ACBCM) addresses the totality of the individual’s existence by acknowledg- ing “that the best prevention strategy is a plan that promotes positive development rather than prevents a particular dysfunc- tional behavior.”^6(p118) Components incorporate individual and relational responses to oppressive structural forces, including how negative stereotyping and the distortion of one’s group weakens self-regard and group pride and creates internalized oppression, which can express itself in depression, sense of disenfranchisement, psychological sup- pression of risk, silence around sexuality and sexual orientation, and fatalism.

Based on an Africentric theoretical paradigm, the ACBCM⁶ reinstills traditional African and AA cultural values into African- descent people based on the premise that

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AAs, for the most part, survived historically based on Africentric worldviews,values, and traditions of interdependence, collectivism, transformation, and spirituality.⁷ Endorse- ment of Africentric values has been shown to increase self-worth and racial pride and to decrease depression and substance use among AA youth and adults.^6,8–12 Infused in the intervention model, these values form the cornerstone for achieving behavioral change.

THE HEALER WOMEN PREVENTION PROGRAM: CASE EXAMPLE

The Healer Women project is a prevention model for AA women grounded in the ACBCM. The program’s objective is to en- hance the resilient capacity of women so that they are better able to engage in health- promotion and life-sustaining activities.

Behavioral change is targeted in the context of

• cognitive restructuring (changing the way women think and feel about them- selves and the world),

• cultural realignment (reinstilling traditional “cultural” values in women to in- fuse protective factors), and

• character development (reconfiguring the way women think about health and well-being).

PARTICIPANTS

Participants were 45 AA women (30 in treatment group and 15 in control group) per year over 2 years.

The program comprised 2-hour sessions each week for 16 weeks. Trained AA facil- itators deliver the intervention (behavioral skills practice, group discussions, lectures, role-playing, prevention video viewing, and take-home exercises) in a community-based setting. Key program components include the following: Understanding the History and Sur- vival of African Americans; Meaning of Being a Black Woman; Collective Meaning in Commu- nity; HIV: Facts, Transmission, and Control;

Substance Abuse: Underlying Dynamics and

Recovery; Forming an Attitude of Health Pro- motion and Disease Prevention; and Where Do I Go From Here?—Forming a Path and a Plan.

OUTCOME EVALUATION

The program will be evaluated on a quasi- experimental group pre–post design with an intervention and a comparison group. It is an- ticipated that program participants will experience the following:

• Increased sense of self-empowerment (as measured in terms of motivation for change, sense of control over one’s life, self-worth, and perception of future quality of life)

• Reduction in sense of disenfranchisement and negation (as measured by decreases in depression, sense of fatalism, and sense of hedonism)

• Enhancement of coping skill (as measured by knowledge about methods of HIV transmission, attitudes toward HIV, and perception of present quality of life)

• Improved life management skills (as measured by intentions to change sexual behavior and decrease in feelings of hopelessness)

• Reduction in HIV/STD risk-taking behavior (as measured by decreased sexual risk- taking behavior)

• Reduction in the incidence and level of substance use (as measured by attitudes toward drugs and decrease in the number of days used drugs)

• Positive changes in the behavioral and attitudinal indicators of the character of Black females (as measured by increased sense of human authenticity and sense of veneration)

SUMMARY

Innovative programs are needed to reduce the incidence rate of HIV infection among AA women, particularly marginalized, resource-poor AA women. The strength of

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Research Letters S111 the African-centered approach is its reflection

of the true life circumstances of AA women.

Targeted changes for outcome measures address core barriers to HIV prevention (eg, poor self-worth, fatalism, depression, poor perception of future quality of life) in or- der to increase a person’s vigilance around

health promotion and reduce high-risk behavior. Studies documenting the utility of infusing African-centered values in prevention tech- niques as protective factors against drug use among AA youth and adults support the use of such programs in HIV prevention for AA women.

REFERENCES

1. Centers for Disease Control and Prevention.

HIV/AIDS Surveillance Report. Rockville, MD: US Dept of Health and Human services; 2004.

2. Gilbert DJ. The sociocultural construction of AIDS.

In: Gilbert DJ, Wright EM, eds. African-American Women and HIV/AIDS: Critical Responses.West- port, CT: Praeger Publishers; 2003:5–27.

3. Beatty L, Wheeler D, Gaitor J. HIV prevention research for African Americans: current and future directions. Journal of Black Psychology.

2004;30(1):40–58.

4. DiClemente RJ, Wingood GM. A randomized con- trolled trial of an HIV sexual risk reduction intervention for young African-American women.JAMA.

1995;274(16):1, 271–276.

5. Wingood G, Diclemente R. Enhancing adoption of evidence-based HIV interventions: promotion of a suite of HIV prevention interventions for African American women.AIDS Education and Prevention.

2006;18(4, suppl A):161–170.

6. Nobles W, Goddard L. Toward an African-centered model of prevention for African American youth at high risk. In: Goddard LL, ed.An African-Centered Model of Prevention for African American Youth at High Risk. Rockville, MD: USDHHS/PHS/SAMHSA;

1993:115–129.

7. Asante MK.Afrocentricity. Trenton, NJ: Africa World Press; 1988.

8. Belgrave FZ, Brome DR, Hampton C. The contri- bution of Afrocentric values and racial identity to the prediction of drug knowledge, attitudes, and use among African American youth. Journal of Black Psychology.2000;26(4):386–401.

9. Belgrave F, Townsend T, Cherry V, Cunningham D.

The influence of an Africentric worldview and demographic variables on drug knowledge, attitudes, and use among African American youth.Journal of Com- munity Psychology. 1997;25(5):421–433.

10. Brook J, Pahl K. The protective role of ethnic and racial identity and aspects of an Africentric orientation against drug use among African Ameri- can young adults. Journal of Genetic Psychology.

2005;166(3):329–345.

11. Harvey A, Hill R. Africentric youth and family rites of passage program: promoting resilience among at-risk African American youths.Social Work.

2004;49(1):65–74.

12. Grills C. Substance abuse and African Americans:

the need for Africentric-based substance abuse treatment models. In: Gilbert DJ, Wright EM, eds.African- American Women and HIV/AIDS: Critical Respon- ses.Westport, CT: Praeger Publishers; 2003:51–72.

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How the Brain Controls

Puberty, and Implications for Sex and Ethnic Differences

Sonya M. Hughes; Andrea C. Gore, PhD

P

UBERTY in girls occurs at an earlier age in the 21st century than it did 100 years ago, particularly in African American (AA) girls. By understanding the biological basis of puberty through laboratory studies and epidemiologic analyses, we may be able to begin to address this issue in the underserved population of AA adolescent girls.

THE NEUROBIOLOGY OF PUBERTY Pubertal development in humans is mani- fested by changes in secondary sex characteristics in the body, including genital and breast development, the first appearance of axillary hair, and changes in body shape and compo- sition. However, it is becoming increasingly clear that the pubertal process in mammals is stimulated by gonadotropin-releasing hormone (GnRH), produced in about 1,000 cells in the hypothalamus.¹GnRH is released from hypothalamic neurons in pulses of approximately hourly intervals, into a small capil- lary system that leads to the anterior pituitary.

At the pituitary, GnRH regulates the release of 2 additional hormones released to control the synthesis and release of gonadal steroid hormones (estrogens, progestins, and andro-

From the College of Liberal Arts (Ms Hughes) and the College of Pharmacy and the Center for Women &

Gender Studies (Dr Gore), The University of Texas at Austin.

Corresponding author: Sonya M. Hughes, College of Lib- eral Arts, The University of Texas at Austin.

gens) and gametogenesis (sperm production in males, ovum production in females). While all 3 levels of this hypothalamic–pituitary–

gonadal (HPG) axis must function for puberty to progress, the activation of neural GnRH cells is the primary driver.¹

Prior to the activation of the HPG axis in infancy and childhood, GnRH secretion is minimal.² At the onset of puberty in both males and females, pulsatile GnRH release in- creases significantly. Although it is not possible to measure GnRH release directly in humans, animal models have demonstrated how GnRH pulses change during puberty. Studies with rhesus monkey models show that prior to puberty, GnRH pulses are extremely small, occur at very low frequency, and increase in frequency and amplitude during subsequent pubertal development.³These changes drive pubertal changes in pituitary and gonadal hormones.

SEX DIFFERENCES IN THE TIMING OF PUBERTY

Significant sex differences have been docu- mented in the timing of puberty in humans.

Puberty in American girls is associated with breast development, which occurs at an average age of 10.5 years, and menarche (first menses), occurring at 12.8 years when aver- aged for all races.²Puberty in boys, which occurs slightly later, is associated with increased testicular size.²Such sex difference also exists in rodent models.⁴In our laboratory, we find that the timing of puberty differs in males and females, with the achievement of adult reproductive function occurring later in male ro- dents, as in humans.¹

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Research Letters S113 Disorders and effects of disruptions of pu-

berty are also sexually dimorphic. Delayed puberty (the lack of development considered normal for pubertal age) is more prevalent in males than in females; precocious or early puberty⁵ is more common in females. The demographics of puberty have also shifted over the past century. The timing of puberty in girls has undergone a dramatic advance, while it has not changed very much for boys during this time.⁶Hygienic and environmen- tal improvements are thought to contribute, though it does not explain why male puberty seems unaffected.⁶Nutritional standards have also improved, with increased obesity among children, which may also contribute to earlier puberty in girls, as fatty tissues accu- mulate estrogens, which are important for sex development.^6,7Boys who are overweight show delayed development when compared to boys of average weight.⁸ Other environ- mental factors also need to be considered to elucidate this sex difference in the timing of puberty.

Rodent models provide insights into mechanisms for the sex differences for puberty.

Treatment of prepubertal rats with a drug to block the effects of GnRH on its pituitary gland target cells caused delayed puberty in male but not female rats.⁹Surprisingly, effects of this drug on male reproduction were ob- served weeks after treatment had ceased. The effect was reversible but took up to a month for males to regain reproductive capacity.

Rodent results are consistent with human findings for a higher prevalence of delayed puberty in males, and experimental studies from

our laboratory and others allow us to better understand these processes in humans.

ETHNIC DIFFERENCES IN PUBERTY The overall trend for earlier puberty in the last century is especially prevalent in AA girls, with Mexican Americans having puberty at an intermediate age.¹⁰ On average, AA girls go through puberty 1–1.5 years earlier than White girls (∼age 9 years for AAs,∼10–10.5 years for Whites for breast development and the first appearance of pubic hair).¹⁰ Menar- che, the first menstrual period, occurred at age 12.16 in AA and 12.88 in White girls.¹⁰ The reason for these racial differences is not well understood, but ethnic differences in food consumption and usage of products that contain estrogens are both possible factors.

Several studies have noted that AA girls are larger in size prepubertally, which is thought to contribute to earlier development.¹¹ The standards for precocious puberty have had to change to reflect these demographic trends.

In females, puberty is now said to be precocious if it occurs before the age of 7 in White girls and the age of 6 in AA girls.⁵ Although precocious puberty may be considered be- nign, it may result in psychological or social problems and earlier sexual activity.⁵Regard- less of species, sex, or race, the precipitating factor for puberty is a change in the brain’s release of the GnRH. This is a consideration for interventions for extremely early or late puberty, as pharmaceutical agents that stimulate or delay inappropriately late or early puberty are already in use.

REFERENCES

1. Gore AC. Modulation of the GnRH gene and onset of puberty. In: Bourguignon JP, Plant TM, eds.Control of the Onset of Puberty. Amsterdam: Elsevier; 2000:25–

35.

2. Pinyerd B, Zipf WB. Puberty—timing is everything!

Journal of Pediatric Nursing. 2005;20:75–82.

3. Terasawa E. Luteinizing hormone-releasing hormone (LHRH) neurons: mechanism of pulsatile LHRH release. Vitamin Hormones. 2001;63:91–

129.

4. Gore AC, Roberts JL, Gibson MJ. Mechanisms for the regulation of gonadotropin-releasing hormone gene expression in the developing mouse.Endocrinology.

1999;140:2280–2287.

5. Kaplowitz PB. Precocious puberty: update on secular trends, definitions, diagnosis, and treatment.Ad- vances in Pediatrics. 2004;51:37–62.

6. Papadimitriou A. Sex differences in the secular changes in pubertal maturation. Pediatrics.

2001;108:E65.

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7. Rogol AD, Roemmich JN, Clark PA. Growth at puberty. Journal of Adolescent Health. 2002;31:192–

200.

8. Wang Y. Is obesity associated with early sexual maturation? A comparison of the association in American boys versus girls.Pediatrics. 2002;110:903–910.

9. Hughes SM, Yin W, Gore AC. The GnRH antagonist acyline delays puberty and suppresses the reproductive axis of male but not female rats. In: Program and abstracts of the Endocrine Society; 2006; Boston, MA.

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