Education and physical activity mediate the relationship between ethnicity and cognitive function in late middle-aged adults.
OBJECTIVE
Minority status has been implicated as a risk factor for disparate scores on cognitive function tests in older adults. Research on ethnicity and cognitive function has yielded socioeconomic status, particularly education, as a primary reason for the discrepancy. Other factors, such as physical activity may provide insight into the relationship. Despite this knowledge, few studies have thoroughly examined the mediating characteristics of education or physical activity in the relationship between ethnicity and cognitive function in younger aged groups. Most research conducted focuses only on older adults during a time when degeneration of brain tissue may complicate the exploration of the relationships among ethnicity and cognitive function. The current research will expand existing knowledge about education, physical activity, and cognitive function in minority groups.


METHODS
The study presents data from the Health and Retirement Study, a nationally representative sample of late middle-aged White, Black, and Hispanic adults (n=9204, mean age+/-SD = 55.8+/-3.1). Regression and mediation testing determined the mediating effects of education and physical activity in the relationship between ethnicity and cognitive function.


RESULTS
Significant association between White ethnicity and higher scores on cognitive tests was evident as early as late middle age. The magnitude of the association significantly diminished on adjusting for education and leisure time physical activity.


CONCLUSIONS
Our data suggest a potential mediating role of education and physical activity on the ethnic differences in cognitive tests in late middle-aged White, Black, and Hispanic adults. Our findings suggest a need for studies to understand if adult education and culturally appropriate physical activity interventions in middle age influence ethnic disparities in prevalence of cognitive impairment in old age.
Masel
Meredith C
MC
Center to Eliminate Health Disparities, University of Texas Medical Branch, Galveston, TX, USA. mcmasel@utmb.edu
Raji
Mukaila
M
Peek
M Kristen
MK
D044383:Black People; D015992:Body Mass Index; D010054:Brief Psychiatric Rating Scale; D003072:Cognition Disorders / Q000208:ethnology* / Q000523:psychology; D004522:Educational Status; D015444:Exercise; D005260:Female; D006304:Health Status; D006630:Hispanic or Latino; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008569:Memory Disorders / Q000208:ethnology* / Q000523:psychology; D008875:Middle Aged; D014481:United States; D044465:White People; D001741:Black or African American
JAMA. 2004 Sep 22;292(12):1454-61
15383516
Neurology. 1999 Dec 10;53(9):1942-7
10599762
Am J Public Health. 1999 Jan;89(1):95-7
9987476
Am J Epidemiol. 1995 Jan 1;141(1):41-9
7801965
Ann Intern Med. 2006 Jan 17;144(2):73-81
16418406
J Gen Intern Med. 2005 Mar;20(3):259-66
15836530
Control Clin Trials. 2001 Aug;22(4):453-79
11514044
Am J Geriatr Psychiatry. 2005 Nov;13(11):968-75
16286440
Am Psychol. 1997 Jun;52(6):613-29
9174398
Radiology. 2003 Dec;229(3):632-5
14657300
Int Psychogeriatr. 2002 Sep;14(3):273-89
12475088
Psychol Aging. 1995 Dec;10(4):578-89
8749585
Am J Public Health. 1996 Jan;86(1):62-6
8561244
Arch Neurol. 2005 Oct;62(10):1556-60
16216938
Ann Epidemiol. 1993 Jan;3(1):71-7
8287159
Epidemiology. 1997 Nov;8(6):621-8
9345660
Am J Epidemiol. 2003 Feb 15;157(4):327-34
12578803
Neurology. 2004 Dec 28;63(12):2316-21
15623693
J Am Geriatr Soc. 2003 Feb;51(2):178-83
12558713
JAMA. 2002 Jan 16;287(3):356-9
11790215
Med Care. 2006 Nov;44(11 Suppl 3):S10-6
17060816
Aging Ment Health. 2003 Mar;7(2):83-102
12745387
Behav Res Methods Instrum Comput. 2004 Nov;36(4):717-31
15641418
J Pers Soc Psychol. 1986 Dec;51(6):1173-82
3806354
J Gerontol B Psychol Sci Soc Sci. 1998 May;53(3):P201-8
9602835
Arch Intern Med. 1996 Jan 8;156(1):93-8
8526703
Contemp Educ Psychol. 2001 Jul;26(3):291-310
11414722
J Int Neuropsychol Soc. 2002 Mar;8(3):341-8
11939693
Am J Epidemiol. 1988 Nov;128(5):1084-101
3189282
Med Care. 2007 Apr;45(4):300-7
17496713
Int J Geriatr Psychiatry. 1999 Jun;14(6):481-93
10398359
J Pers Soc Psychol. 1995 Nov;69(5):797-811
7473032
Mayo Clin Proc. 2003 Oct;78(10):1290-308
14531488
J Health Soc Behav. 1995;Spec No:80-94
7560851
Ann Epidemiol. 1995 Jan;5(1):76-8
7728289
J Gerontol B Psychol Sci Soc Sci. 2001 Sep;56(5):S266-74
11522808
J Am Geriatr Soc. 2003 Apr;51(4):459-65
12657064
J Clin Epidemiol. 1999 Nov;52(11):1095-102
10527004
Lancet Neurol. 2006 Sep;5(9):735-41
16914401
Neurology. 2004 Dec 28;63(12):2322-6
15623694
Ann Intern Med. 2008 Mar 18;148(6):427-34
18347351
J Gerontol B Psychol Sci Soc Sci. 2005 Sep;60(5):P242-50
16131618
Ann Epidemiol. 1995 Jan;5(1):1-7
7728280
Arch Neurol. 2001 Dec;58(12):1985-92
11735772
J Community Health. 1999 Oct;24(5):359-79
10555925
J Am Geriatr Soc. 2007 May;55(5):758-62
17493197