乌鸦传媒

Vigorous exercise appeared to preserve cognitive function in older adults with hypertension, a post hoc analysis of SPRINT MIND trial data showed.

At least one vigorous physical activity session per week reduced the risk of future mild cognitive impairment and probable dementia for people with hypertension over 4.5 years of follow-up, reported Richard Kazibwe, MD, of Wake Forest University School of Medicine in Winston-Salem, North Carolina, and co-authors.

Participants who had one or more vigorous physical exercise sessions weekly had a significantly lower risk of mild cognitive impairment (HR 0.80, 95% CI 0.67-0.95) and a composite of mild cognitive impairment/probable dementia (HR 0.82, 95% CI 0.70-0.94) compared with those who had less than one vigorous session a week, Kazibwe and colleagues wrote in .

Higher vigorous physical activity trended toward a lower risk of probable dementia, but the relationship didn't reach statistical significance (HR 0.80, 95% CI 0.63-1.02).

"We know that physical exercise offers many benefits, including lowering blood pressure, improving heart health, and potentially delaying cognitive decline," Kazibwe said in a statement. "However, the amount and the intensity of exercise needed to preserve cognition is unknown."

Many epidemiological studies support the role of lifestyle in dementia risk. In 2020, the Lancet Commission reported that up to 40% of dementia cases may be prevented or delayed by modifying 12 risk factors, including physical inactivity. Studies of U.K. Biobank participants have linked moderate and vigorous exercise with midlife cognition, and sedentary lifestyles in older adults with incident dementia.

Hypertension is associated with an increased risk of cognitive impairment. In their analysis, Kazibwe and co-authors evaluated data from 7,670 people who participated in the SPRINT MIND substudy of the SPRINT randomized clinical trial. The SPRINT trial was stopped early when its primary outcome showed a significant benefit of intensive systolic blood pressure treatment compared with standard treatment.

The SPRINT MIND substudy showed that treating hypertensive older adults to a systolic blood pressure goal of less than 120 mm Hg, compared with treating them to a goal of less than 140 mm Hg, reduced the risk of probable dementia by 17%, a statistically non-significant difference. Intensive blood pressure control showed statistically significant benefits in secondary outcomes, including a 19% lower rate of mild cognitive impairment.

At enrollment, SPRINT participants were asked about their frequency of vigorous-intensity physical activity over the past 12 months. The researchers categorized vigorous physical activity into two groups: less than one session per week (low activity group), and one or more sessions per week (high activity group). Participants with significant limitations in physical function or missing data were excluded from the post hoc analysis.

Mean participant age was 68 years, 34.5% were women, and 59.6% were white. Kazibwe noted that nearly 60% of study participants reported vigorous activity at least once a week, even those ages 75 and older. This "suggests that older adults who recognize the importance of exercise may be more inclined to exercise at higher intensity," he observed.

Over a maximum follow-up of 7.4 years (median 4.5 years), 570 mild cognitive impairment events, 273 probable dementia events, and 759 mild cognitive impairment/probable dementia events were reported.

Among participants in the high activity group compared with the low activity group, the incidence of mild cognitive impairment events was 6.5% versus 8.8%, 3.1% versus 4.3% for probable dementia events, and 8.7% versus 11.7% for mild cognitive impairment/probable dementia events.

Compared with participants in the low activity group, those in the high activity group experienced lower event rates per 1,000 person-years of mild cognitive impairment (13.9 vs 19.7), probable dementia (6.3 vs 9.0), and mild cognitive impairment/probable dementia (18.5 vs 25.8). Overall, the protective relationship between vigorous exercise and cognitive outcomes was more pronounced for people under age 75.

In the post hoc analysis, participants in the SPRINT intensive and standard blood pressure treatment groups had comparable results for the relationship between vigorous physical activity and risk of cognitive outcomes.

The study had several limitations. The relatively fewer cases of probable dementia might mean the study lacked statistical power to detect whether vigorous activity influenced its risk, the researchers noted. In addition, all physical activity was self-reported at baseline.

"While this study provides evidence that vigorous exercise may preserve cognitive function in high-risk patients with hypertension, more research is needed to include device-based physical activity measurements and more diverse participant populations," Kazibwe said.

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