Coaching is not just for athletes. People on the brink of dementia might stand to benefit from an occasional pep talk, too. According to the results of a behavioral intervention trial published September 10 in JAMA Neurology, receiving regular visits from health care workers who helped set healthy lifestyle goals staved off cognitive decline in African-Americans with mild cognitive impairment. This goal-oriented intervention worked better than simply receiving supportive social visits. African-Americans have nearly twice the rate of dementia as whites.
- Goal-oriented lifestyle coaching tested in African-Americans with MCI.
- The coached group had less decline in memory and daily functioning.
- Nearly twice as many people in an uncoached group progressed to dementia.
Despite the study’s limitations—notably a lack of biomarker data to ascertain the cause of MCI among participants—its finding supports the idea that behavioral interventions slow decline in this high-risk population, the authors contend.
Explanations for the elevated dementia risk in blacks abound, including higher rates of cardiovascular disease and diabetes, lower socioeconomic status and education, genetic differences, and poor access to health care. For these reasons, researchers led by Barry Rovner at Jefferson Hospital for Neuroscience in Philadelphia tailored a behavioral-intervention study to the needs of this population. In particular, the researchers wanted to test whether promoting cognitive, social, and physical activity among black people with MCI might slow the onset of dementia.
Participants were recruited from senior centers, homes, churches, and primary care clinics in Philadelphia. They were invited to join if they identified as black, were at least 65 years old, and had amnestic MCI based on criteria from the National Institute on Aging and the Alzheimer’s Association. A total of 221 enrolled and were randomized to receive the behavioral intervention or supportive visits as a control. Participants in both groups received regular in-home visits from black health care workers over two years. Making sure that the workers were also black was crucial to promote trust between the participants and their visitors, Rovner said.
In the treatment group, participants underwent so-called “behavioral activation.” This means the health care workers set goals and action plans to boost cognitive, social, and physical activity. Rovner noted that the participants were free to choose which types of activities they wanted to pursue. A majority opted to concentrate on boosting their cognition through reading, cooking, and playing word games. In the supportive-therapy group, participants received friendly visits from community health care workers, as well, but did not set goals or chart plans for behavioral change. All participants received cognitive and functional assessments at six, 12, 18, and 24 months. In all, 164 people completed the study, 77 in the behavioral activation group. Men were more likely to drop out than women, but no other factors, including severity of MCI, distinguished people who completed the trial from those who did not.
The primary outcome was the incidence of cognitive decline at 24 months. “Decline” was defined as a drop in at least six points on the Hopkins Verbal Learning Test–Revised (HVTL-R) compared with baseline scores. The researchers included data from all participants who had at least one follow-up assessment. They found that the relative risk for cognitive decline in the intervention versus control group decreased with each time point. The ratio of decliners in the behavioral-activation group to decliners in the supportive control group was 1.16 at six months, 0.7 at 12 months, 0.37 at 18 months, and a scant 0.12 at 24 months. At 24 months, only one out of 77 people in the behavioral-activation group scored less than six points below their baseline scores, while nine of 87 people in the supportive-therapy group did.
Throughout the study, four out of 90 participants in the behavioral-activation group who had at least one follow-up visit progressed to dementia, while eight out of 95 participants in the supportive-therapy group did.
The data were far from cut and dried, however. Notably, some participants scored within the declining range (i.e., six points below baseline on the HVLT-R) at one visit, but not at the next. People in the behavioral-activation group scored as decliners on about half as many visits as those in the supportive-therapy group. Considering HVLT-R scores as a continuous variable, people in the behavioral-activation group actually improved scores by an average of 26 percent per year, while those in the control group had no change. These rates of decline are strikingly low for both groups, especially when compared with the 12 percent to 41 percent decline in memory reported for black people with MCI over two years in other epidemiological studies (Gao et al., 2014; Lee et al., 2012; Shadlen et al., 2006). People in the behavioral-activation group also improved on tests of executive function, while those in the control group did not.
Rovner acknowledged the need for further study. He added that the findings could indicate that both interventions—behavioral activation and supportive therapy—slowed cognitive decline. Without a true control group that received no treatment whatsoever, it is difficult to tell.
Rovner noted another result that could have more real-world significance than memory test scores. Participants in the behavioral-activation group were stable throughout the study on the University of California Performance-Based Skills Assessment, which measures a person’s ability to carry out daily tasks such as household upkeep, making phone calls, and taking public transportation. The supportive-therapy group slipped on this functional test during the two-year study.
Walter Kukull of the University of Washington in Seattle wrote that the study was interesting, but expressed concern about the lack of data reported on the randomization of study groups. “For a randomized controlled trial, one expects that a variety of important risk factors or determinants of cognitive decline or its measurement (APOE, education, existing vascular and neurodegenerative pathology) would be distributed equally, if randomization worked and if these factors did not also influence dropout,” he wrote. “I would be more convinced if they could verify that some of these risk factors were actually equally distributed by randomization, and that dropout was not also leading to ‘reverse causation’ inference,” he added. When the people who drop out of a study are the unhealthiest, the final outcome can appear more positive than reality.
Hugh Hendrie of the Indiana University School of Medicine in Indianapolis noted that though the findings suggest the intervention slowed decline on test scores, the clinical significance of those results is uncertain. Despite some caveats, though, he still thinks the study confirms the “engagement hypothesis,” i.e., the idea that exercise, cognitive, and/or social activities preserve health in a population that is particularly vulnerable to dementia (see comment below).—Jessica Shugart
- Gao S, Unverzagt FW, Hall KS, Lane KA, Murrell JR, Hake AM, Smith-Gamble V, Hendrie HC. Mild cognitive impairment, incidence, progression, and reversion: findings from a community-based cohort of elderly African Americans. Am J Geriatr Psychiatry. 2014 Jul;22(7):670-81. Epub 2013 Jul 3 PubMed.
- Lee HB, Richardson AK, Black BS, Shore AD, Kasper JD, Rabins PV. Race and cognitive decline among community-dwelling elders with mild cognitive impairment: findings from the Memory and Medical Care Study. Aging Ment Health. 2012;16(3):372-7. Epub 2011 Oct 14 PubMed.
- Shadlen MF, Siscovick D, Fitzpatrick AL, Dulberg C, Kuller LH, Jackson S. Education, cognitive test scores, and black-white differences in dementia risk. J Am Geriatr Soc. 2006 Jun;54(6):898-905. PubMed.
- Rovner BW, Casten RJ, Hegel MT, Leiby B. Preventing Cognitive Decline in Black Individuals With Mild Cognitive Impairment: A Randomized Clinical Trial. JAMA Neurol. 2018 Dec 1;75(12):1487-1493. PubMed.